This invention relates in general to tissue manipulating mechanisms useful in surgery and other medical procedures and, more particularly, to a mechanism for grasping tissue atraumatically.
Most medical gripping devices operate much like a pair of scissors or forceps whereby two jaw members move angularly relative to one another about a pivot axis and come together gradually toward the open end. At the pivot end, pinching is positive, while the open end may not come together sufficiently to grasp the desired amount of tissue. In other words, the jaws come together always at an angle. A considerable advantage is to be gained by gripping mechanism where the actual elements which engage the tissue come together in parallelism.
Historically, most medical operations have been performed employing the "open" procedure whereby exterior tissue of the patient is opened and peeled back to expose a relatively large area sometimes including the patient's organs and the like. With this large operative field, the size of surgical instruments is not as important as it is with the newer and more efficient technique of endoscopic surgery. In the endoscopic procedure, one or more small openings are made in the exterior tissue and a small light at the end of a fiber optic is inserted along with a lens also connected by a fiber optic to a video camera. This permits the surgeon to view on a scope what he could not otherwise see. Through one or more additional small openings, the surgeon inserts instruments such as tissue grasping mechanisms, cutting devices and the like which, by their very nature, must be of a small enough diameter to be inserted through the small openings. Some of these instruments are expanded when they are located inside the patient, whereupon the surgeon performs the necessary procedures viewing everything on the scope. The instruments are then withdrawn and only the small incisions have to be closed. Thus, a tissue grasping device which operates with the grasping elements operating in parallel has its value further enhanced if the instrument is collapsible to be able to be inserted through a small aperture and once having been located within the patient at the operative field is expandable to a functional position.
The clamping action of a device which can grasp tissue atraumatically is useful in numerous medical applications. For example, when searching for air leaks in a lung, tissue is placed under water, by flooding the area with saline, and then clamped until bubbles are observed to stop. A clamp of the desired type is easily positioned around the lung for this procedure. A line of staples may then be applied to close off the leaking portion of the lung.
If it is desired to roll a portion of a lung in order to plicate or layer it to receive a line of staples, a composite device having a plurality of parallel tines or gripping elements is desirable. It is advantageous to grasp the lung tissue with opposable, parallel tines and then rotate the device to roll the tissue over the tines.
In another application, when applying staples to lung tissue, it is desirable to remove the air from the tissue as, for example, to collapse it such that a stapler with limited jaw size can be applied.
A grasper having opposable tines is beneficial to this operation by rotating the instrument to squeeze the air out of the lung.
Emphysematous blebs can cause at least two problems. One is pneumothoraces as the bleb leaks and the other is obtrusive disease as the bleb or emphysematous tissue overfill the chest. Frequently, both of these diseases are treated by resuction of the diseased lung or by plication. In the plication technique, the lung tissue is rolled and a non-cutting stapler is placed over the layers of lung held by a clamp. A stapler is positioned over the plicated tissue and the grasping mechanism is withdrawn. The stapler is then fired and the tissue remains in place but the bleb has been sealed or the volume of the lung has been reduced without removing any tissue.
One of the largest causes of death in the United States at the present time is attributed to the final stages of emphysema. It is generally believed that lung volume reduction surgery can be of substantial benefit in addressing the physiologic problem (air flow limitation).
Lung volume reduction surgery alone is not the answer. Rehabilitation or conditioning programs are limited by air flow reduction to the lungs. The surgery is intended to improve air flow by changing the mechanical relationship between the lung, chest, wall and diaphragm which does result in improved exercise tolerance. Consequently, lung reduction surgery is most beneficial to patients who are participating in rehabilitation. It is particularly beneficial to patients with hyperexpanded lungs and chest wall associated with air flow obstruction.
While the present invention contemplates a device having general surgical applications, it will be illustrated in lung plication. One of the ways to reduce or eliminate the effects of emphysema is to reduce the size of the diseased lung. This can be done by stapling it, i.e., folding it and then securing it in its folded position. A reduction in volume of 30% has been found to be beneficial, particularly when accompanied by a reconditioning program. The present invention is directed to a device for reducing the size of the lung by grasping it with an atraumatic device, rolling a portion of the lung upon itself and exposing the portion to be stapled.